Disk drives using various kinds of media, such as optical disks, magneto-optical disks, flexible magnetic-recording disks, and similar disks for data-storage are known in the art. In particular, hard-disk drives (HDDs) have been widely used as data-storage devices that have proven to be indispensable for contemporary computer systems. Moreover, HDDs have found widespread application to moving image recording and reproducing apparatuses, car navigation systems, cellular phones, and similar devices, in addition to computers, due to their outstanding information-storage characteristics.
Magnetic-recording disks used in HDDs have multiple concentric data tracks and servo tracks. Each servo track includes multiple servo data that include address information. Each data track includes multiple data sectors that include user data. Data sectors are recorded between the servo data located at discrete locations along the circumferential direction of a track. A magnetic-recording head incorporated in head-slider supported by a rotary actuator accesses a desired data sector of a track determined by address information contained in servo data to write data to, or alternatively, to read data from, the data sector.
A head-slider is bonded on a suspension of an actuator. The pressure caused by air viscosity between an air bearing surface (ABS) of the head-slider facing a magnetic-recording disk and the spinning magnetic-recording disk balances the pressure applied by the suspension toward the magnetic-recording disk so that the head-slider flies in proximity to the recording surface of the magnetic-recording disk with a certain fly height. The actuator rotates on a pivot shaft to move the head-slider to a target data track and positions the head-slider over the track. The magnetic-recording disk is secured to a spindle motor; and, the magnetic-recording disk, or alternatively, the head-slider, may acquire an electrical charge, for example, through tribo-electricity generated between a rotating magnetic-recording disk and a head-slider flying in proximity to the recording surface of the magnetic-recording disk, when the spindle motor rotates the magnetic-recording disk. Engineers and scientists engaged in the development of magnetic-recording technology are interested in developing procedures to control the affects of the build-up of the electrical charge because electrical charge may cause an electrical discharge between the magnetic-recording disk and the head-slider that affects the high levels of reliability demanded by the market for HDDs.